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Re: MySQL 5.5 Slow performance to insert




----- Original Message -----
> From: "Camilo Vieira" <camilo.vieira@xxxxxxxxx>
> Subject: Re: MySQL 5.5 Slow performance to insert

> $ ./mysqltuner.pl --user root --pass abril@123

Thank you for that password :-) I don't particularly like MySQLtuner myself, it makes assumptions about your workload that are, imo, false more often than not. Anyway...

> [!!] Total fragmented tables: 284

*shrug* Small issue on modern storage, pretty much no issue on solid state.

> [!!] Key buffer used: 18.2% (3M used / 16M cache)

*shrug* You could shrink that if you have no MyISAM at all, but it's a neglectable amount of memory.

> [!!] Query cache is disabled

Which is pretty much irrelevant for an insert workload :-)

> [!!] Table cache hit rate: 1% (400 open / 30K opened)

That might be worth growing. Exact numbers are hard to point at, use munin or similar to figure out the growth rate of opened_tables.

> [!!] InnoDB  buffer pool / data size: 4.0G/52.4G

If possible, size your buffer pool to at least your active dataset. This will have a considerable impact on your initial insert speed.

> [!!] InnoDB buffer pool instances: 1

>From 5.6 (I think) this defaults to 8. The benefit is less contention for mutexes and the like. Upgrading to 5.6 is worthwile in most cases anyway.

> [!!] InnoDB Write buffer efficiency: 0.00% (0 hits/ 1 total)

Hmm. That's peculiar for an insert workload... did you run that after (or during) the workload?


Your original mail also doesn't seem to specify the workload beyond 'inserts'. Details?

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